With industrial development and population growth, demand for energy has increased, leading to depletion of petroleum resources and rapid increase in demand for natural gas, which is thought to be more plentiful than petroleum.
Natural gas is classified into sweet gas having a high content of methane and sour gas containing corrosive and toxic hydrogen sulfide. Recently, the number of gas wells capable of supplying sweet gas has gradually decreased.
Accordingly, although development of stranded gas wells generating sour gas has been avoided due to low economic efficiency, demand for development of the stranded gas wells is gradually increasing.
In development of the stranded gas well, apparatuses and plants for separating carbon dioxide and hydrogen sulfide gas from sour gas must be installed and constructed. Here, carbon dioxide generated as a by-product in production of natural gas is discharged into the atmosphere or stored underground via conduits.
Therefore, in development of the stranded gas well, an underground storage for storing separated carbon dioxide is necessarily placed near the stranded gas well. Further, if regulations on carbon dioxide emissions are further tightened in the future, development of stranded gas wells using such apparatuses and plants will be impossible without underground storage of carbon dioxide.